STOCK-BASED COMPENSATION (Performance Stock Units) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 158	$ 188	$ 310
Share-based Payment Arrangement, Expense, Tax Benefit	$ 36	$ 42	115
Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	1,173,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 57.58
Actual number of shares granted above target minimum range	0.00%
Actual number of shares granted above target maximum range	200.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,121,000	232,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 57.58	$ 71.16
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(232,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 71.16
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(52,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 57.58
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 18	$ 0	202
Employee Service Share-based Compensation, Tax Benefit Realized from Vesting of Performance Deferred Stock Awards	4	0	75
Share-based Payment Arrangement, Expense	25	12	106
Share-based Payment Arrangement, Expense, Tax Benefit	$ 6	$ 3	$ 39
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	162,000	0	616,000
Total cash paid to settle PSUs	$ 13	$ 0	$ 38
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 12
Employee Service Share-based Compensation, Nonvested, Total Compensation Cost not yet recognized and period for recognition in years	1 year 10 months 9 days
Performance Stock Units (PSUs) [Member] \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	1 year
Performance Stock Units (PSUs) [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
April 1, 2019 - December 31, 2019 [Member] \| Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	1,173,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 57.58
September 1, 2017 - August 31, 2019 [Member] [Member] \| Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			232,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 71.16
January 1, 2016 - December 31, 2018 [Member] \| Performance Stock Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			1,728,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 81.99

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Employee Service Share-based Compensation, Tax Benefit Realized from Vesting of Performance Deferred Stock Awards

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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